Mercury co-benefits of climate policies on rice mercury concentration and exposure in China

Abstract

In China, both climate mitigation policies under the Paris Agreement and mercury controls under the Minamata Convention affect mercury emissions, which may result in health benefits for those who consume rice. Here, we examine the influence of Chinese climate and mercury policy on rice mercury concentrations. A China regional economic model is used to construct mercury and climate policy relevant future mercury emission scenarios. A global scale atmospheric chemistry transport model and a rice paddy biogeochemical cycle model for mercury are used to simulate mercury emissions and deposition to Chinese rice paddies, and to simulate the resulting rice mercury concentrations, respectively. Our preliminary results suggest that mercury policy is more effective in mitigating rice mercury level compared to climate policy. Mercury co-benefits of climate policies on rice mercury level is at least as twice as high compared to mercury policy alone. Potential influences and mercury co-benefits of climate policies on rice mercury level at provincial level in China are also discussed.